Introduction to the application of event-related potentials in cognitive rehabilitation research

In 1875, Richard Caton, a physician and medical lecturer from Liverpool, discovered that brain electrical signals could be recorded directly from the surface of the exposed cortex using a reflecting galvanometer. A half century later, Hans Berger (1929) was able to detect these brain waves with electrodes placed on scalp. He, like Caton, noted that these voltages could be influenced by external events that stimulated the senses.